• Journal of Sensor Science and Technology
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• v.32 no.1
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• pp.31-38
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• 2023

Three-dimensional (3D) micro/nanostructures based on soft elastomers have received extensive attention in recent years, owing to their potential and advanced applicability. Designing and fabricating 3D micro/nanostructures are crucial for applications in diverse engineering fields, such as sensors, harvesting devices, functional surfaces, and adhesive patches. However, because of their structural complexity, fabricating soft-elastomer-based 3D micro/nanostructures with a low cost and simple process remains a challenge. Bio-inspired designs that mimic natural structures, or replicate their micro/nanostructure surfaces, have greatly benefited in terms of low-cost fabrication, scalability, and easy control of geometrical parameters. This review highlights recent advances in 3D micro/nanostructures inspired by nature for diverse potential and advanced applications, including flexible pressure sensors, energy-harvesting devices based on triboelectricity, superhydrophobic/-philic surfaces, and dry/wet adhesive patches.

• Journal of the Ergonomics Society of Korea
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• v.27 no.4
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• pp.45-58
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• 2008

Ergonomic techniques have been required to analyze the effectiveness of functional clothing design improvement in a systematic and analytic manner. The goals of the present study are to: (1) comprehensively and analytically examine the effectiveness of clothing improvement by using the relationship analysis between clothing design components (D) and ergonomic evaluation measures (E) and (2) prove the usefulness of cost-effectiveness analysis for clothing design optimization. The cost effectiveness analysis is comprised of the preliminary evaluation based on expertise and the in-depth evaluation where the D-E relationship analysis is applied. As a result of the cost effectiveness analysis applied to flame-proof clothing, an optimal design was identified by analyzing costs and qualitative/quantitative effects. In the preliminary evaluation, the expected effectiveness of each design alternative on wear efficiency and wear comfort was estimated. In the in-depth evaluation, however, the effectiveness of each design alternative was analyzed by quantitative evaluation in a wearing test using a questionnaire prepared based on the D-E relationship analysis. It was concluded that the D-E relationship analysis and the cost-effectiveness analysis are useful for comprehensive evaluation and optimization of functional clothing design.

• Korean Journal of Mathematics
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• v.6 no.1
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• pp.27-46
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• 1998

We are concerned with an optimal control problem governed by a Poisson equation in which body force acts like a control parameter. The cost functional to be optimized is taken to represent the error from the desired observation and the cost due to the control. We recast the problem into the mixed formulation to take advantage of the minimax principle for the duality method. The existence of a saddle point for the Lagrangian shall be shown and the optimality system will be derived therein. Finally, to attain an optimal control, we combine the optimality system with an operational technique. By achieving the gradient of the cost functional, a convergent algorithm based on the projected gradient method is established.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.244-245
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• 2021

Design VE (Value Engineering) has been basic design and implementation design separately, but due to the recent change in guidelines, it is changing to implement only once in the implementation design stage. However, in the implementation design stage, construction costs, plans, and specifications based on the volume details are almost completed. Therefore, it is effective to perform the function analysis step after identifying information analysis and key issues through CostModeling based on functional center for the selected target in the process of implementing the VE performance procedure.

• The Journal of Society for e-Business Studies
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• v.2 no.2
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• pp.89-113
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• 1997

Modeling methodology has been widely used for analysis and design of a information system. Specially, under the CALS environments, modeling approach is more important because the enterprise functions are inter-related and information sharing speeds up the business. In this paper, we suggest functional requirements about modeling methodology for CALS by surveying the IDEF0 and ARIS. The former is FIPS 183 and the latter is basic methodology of SAP/R3 which is world-wide ERP system. The proposed functional requirements include all semantics of IDEF0 and adds some features. The first is adding modeling components which are semantic representations. In addition to ICOMs, we add the time and cost component which is required to execute the function. The second is tracing mechanism. When we need some information, we drive the functions related with the information by reverse tracing of the function which produces the information as a output and input. Through the tracing, we find out the bottleneck process or high cost process. This approach guarantees the integrity of data by designating the data ownership. Finally, we suggest the final decomposition level. We call the final decomposed function into unit function which has only one output data. We can combine and reconstruct some of functions such as 'lego block' combination.

• Environmental and Resource Economics Review
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• v.10 no.1
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• pp.95-126
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• 2001

Functional values for wastewater treatment and atmospheric regulation in coastal wetland and rice paddy ecosystems are quantified, and an illustration is given on how to integrate biophysical parameters into a valuation framework. This is one of most controversial issues in economic analysis for wetland preservation versus wetland conversion to agricultural use. This paper includes theoretical considerations for estimating functional values of environmental ecosystems, and the integration of biophysical data and replacement cost method employed. Specific physical and geographical characteristics and data on ecosystem functions and services in coastal wetlands and rice paddies are addressed for evaluating their values in economic terms. In particular this paper indicates double counting problems and overestimation in the previous studies, and demonstrates how to avoid them and to maintain the consistency of valuation process involving a least-cost method, thus enables an accurate integration of the coastal wetland ecology and wetland economics. As a result which is far away from the previous studies, the total economic present value of wastewater assimilation by coastal wetland is estimated at 7,484,640 won/ha, and the net present value of positive effect for atmospheric regulation, negative effects for air pollution and water pollution by rice paddy is estimated at -37,934 won/ha, assuming that resources are infinitely long-lived and the annual value and the rate of discount (10%) is constant every year. In conclusion, for further reliability and validity of functional values for natural resources it is very noteworthy that a general equilibrium framework that could directly incorporate the interdependence between ecosystem functions and services would be preferred to the partial equilibrium framework.

• 전기의세계
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• v.28 no.6
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• pp.47-51
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• 1979

An optimal problem in which the dynamics is nonlinear and the cost functional includes a discontinuous integrand is investigated. By using Neustadt's abstract maximum principle, a necessary conditions in the form of Pontryagin's maximum principle is derived and it is further shown that this necessary condition is also a sufficient condition for normal problems with linear-in-the-state systems.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.27.2-27
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• 2001

This paper proposes a receding horizon predictive control (RHPC) for nonlinear time-delay systems. The control law is obtained by minimizing finite horizon cost with a terminal weighting functional. An inequality condition on the terminal weighting functional is presented, under which the closed-loop stability of RHPC is guaranteed, A special class of nonlinear time-delay systems is introduced and a systematic method to find a terminal weighting functional satisfying the proposed inequality condition is given for these systems. Through a simulation example, it is demonstrated that the proposed RHPC has the guaranteed closed-loop stability for nonlinear time-delay systems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.35-44
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• 2018

The purpose of this study was to derive the factors that affect the development cost and the priority/weight of effectiveness in the pre-development stage of a service robot to estimate the development cost. In particular, the functions of service robots vary according to the field of application, and their prices are not only different but most of them are small-scale production; hence, a cost estimation is necessary. In this research, the factors affecting the service robot development cost in the process of service robot development and adding functions are classified as a functional factor while the factors that affect the entire development cost due to environmental causes, in which the service robot is operated or in the development process, are classified as an adjustment factor. The FGI was conducted to derive the factors and a Delphi survey was conducted among 84 domestic experts to determine the weights of the factors. As a result of the analysis, six functional factors (41 detailed criteria) and five adjustment factors (17 criteria) were derived, the cost weight and rank of the factors were suggested. This study suggests that the development cost of the service robot can be used as a decision-making strategy to select the operation functions in the development process, and can be utilized as an essential tool for the service robot development.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.2
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• pp.258-264
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• 2010

Various kinds of ballast water treatment systems (BWTS) have been developed corresponding to reinforced IMO rules for marine environment. Some of them got the certificate of IMO and others are waiting for it. Selection of optimum BWTS is very important. Optimum BWTS means not only functional requirements but also economic efficiency. This paper presents economic analysis model for optimum BWTS according to ship type and size. In this study 10 kinds of BWTS whose initial installation cost and maintenance cost are known are analyzed based on present worth method. It is assumed that all BWTS satisfy minimum functional requirements and we need to consider different economical efficiency. Through the economic analysis we could select optimum BWTS.